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“Spelter Chills.” 370 RIESMAX, boles: SPELTER CIIILES “SPELTER CHILLS."1 By David Riesmax, M.D., ASD Russell S. Boles, M.D., I,HILADF.M,jnA. (From the Medical Division of the Philadelphia General Hospital.) In recent years the results obtained from the study of occupational diseases lias been most gratifying. Such a study not only often aids in arriving at an otherwise difficult diagnosis, but as a part of industrial hygiene it has become of great importance in the pre¬ vention of those ills that arc the result of occupation. With this in mind a systematic study of occupational diseases is being made in the medical division of the Philadelphia General Hos¬ pital, and the affection about to be described is one of a number of interesting conditions revealed by this study. “Spelter chills” is the name given to a condition heretofore but briefly described under such varying terms as brass-founders’ ague, brass chills, zinc chills, smelter shakes, das Giesfiebcr or Staubficbcr, and fitivre des fondeurs. We believe the condition results from the inhalation and ingestion of the fumes and flakes of zinc oxide arising from the melting and volatilizing of spelter, which is the commercial name for zinc in its impure state. Spelter chills wc found to be the name popularly employed among the local workmen. The chills occur in brass foundries, in zinc smelters, and in places where zinc is poured. The majority of instances are found in places where yellow brass is manufactured, a process in which a large percentage of zinc is used. The chills do not occur in those engaged in processes in which the zinc is not volatilized. Lehman produced it artificially in a workman by burning zinc. Some investigators have suspected copper as the cause of the chills. This seems unlikely in view of the fact that in the manufacture of red brass, which con¬ tains a large percentage of copper and a small percentage of zinc, the chills occur less frequently than in the manufacture of yellow brass, which contains a greater percentage of zinc than of copper. In brass workers employed in finishing or polishing of brass, though they in¬ hale quantities of copper-laden dust, as is shown by the excretion of copper in the perspiration imparting a greenish tinge to the skin, hair, and underclothes, the chills never occur. Lead as a contribu¬ tory cause may be considered a negligible factor. A brief description of the process which exposes the workers to 1 Read l»fore the Section on General Medicine of the College of Physicians of Philadelphia, March 27, 1910. niusman*, holes: spelter cmu.s ;*?7 this ailment may he of interest: Zinc is obtained from its ores, zinc sulphide or zinc blende and zinc carbonate or calamine. Brass is ordinarily of two varieties, red and yellow. The red brass, the better quality, is made up of from two to four parts copper and one part zinc. rllie yellow brass is made up, roughly, of three parts copper and two parts zinc. The relative proportions of zinc and copper thus determine the quality of the brass. Brass is manufactured by either the direct or the indirect process, the latter being the safer, though the former is probably in more common use. In the direct process the metals are all fused together at the same time. In the indirect they are fused one after another, the order depending upon the relative fusibility and volatility. The metals are melted in a large crucible, which is first heated to avoid breaking. Into the crucibc is put, first, a mixture of scrap brass or grain copper; rarely are the pure copper and zinc directly mixed in their definite proportions. After the* material is melted down the proper amount of copper or zinc is added to secure the desired com¬ position. It requires 2000° F. to melt copper and 770° F. to melt zinc. Hence the necessity of adding the zinc last. Zinc is readily volatile above 770° F., and for this reason must be well submerged beneath the surface of the melted copper. The mixture is then poured into molds. Though the process up to this point exposes the workmen in some degree to the metallic fumes the pouring is probably the source of greatest danger. As the metal is being poured the atmosphere becomes laden with intensely irritating whitish fumes and fine flaky deposits of zinc oxide or “zinc snow,” as it is called. Sir Thomas Oliver gives the following analysis of this “zinc snow”: Moisture ... Organic matter.39.42 Silicious residue.9_I4 Oxide of line.28.82 Oxide of iron.2.7S Copper.* 7.71 Other matter.. K.49 100.00 Another analysis gives 44.0 per cent. zinc. It is this volatilized zinc or “spelter” impregnating the atmos- phere breathed by the workmen that we think is the cause of the “ spelter chills.” As to their ultimate cause we are not prepared to speak. Lehman believes the symptoms arc due to an auto-intoxica¬ tion from absorption of dead epithelial cells lining the respiratory tract, the cells being destroyed by the inhalation of zinc oxide fumes. Iiambouse says that neither pure copper nor pure zinc gives rise to poisoning, yet the pouring of brass, an alloy of zinc and copper, sets up a peculiar train of symptoms. The question of infection seems doubtful. It is probably an acute intoxication. 37S ItlESMAN, boles: spelter ciiili.s Tlmckmli in England, in 1S30, recognized a definite tmin of symp¬ toms arising from the inhalation of volatilized zinc, hut makes no reference to the chills. Grccnhow in England, in 1S45, described a condition “similar to an intermittent fever of an irregular type.” Hlaudct and Greenhow were also aware of a form of poisoning ob¬ served in brass pourers. The chills themselves seem to have been first observed by Schwitzcr, in Germany, in 1SH2. The observations of Siegel made in YYurttemberg in 1005 are, however, the most val¬ uable on the subject, llarcly has the condition claimed the atten¬ tion of American writers, a few reports of individual cases only having been made in Chicago, in 1904, by Prs. Ungre and Savin and by 1 )r. S. II. 1’ietrowicez. Hr. Kober comments on it in his report to the House Commission. Hr. Hayhurst in his “ Report on the In¬ vestigation of the Brass Manufacturing Industry in Chicago” con¬ tributes the most elaborate American report. Conditions Predisposing to Chills.—Respiratory and circula¬ tory disturbances favor a more sudden and severe onset of the chills. Minors and women and those unaccustomed to the work are more susceptible than others. Alcoholism, anemia, malnutrition, anil impaired renal function likewise constitute predisposing causes. Characteristic of the chills is their tendency to attack the workmen every Monday. This may perhaps be due to the free indulgence in alcohol over the week end. The chills occur most frequently in winter, this undoubtedly being due to the greater accumulation of the fumes in the workshop owing to the windows not being open. Their frequency is further increased on damp, cloudy days on accountof the heavy atmospheric conditions and consequent diffi¬ culty in clearing the room of the fumes. Description oftiie Attack.—The chill may begin while the man is at his work in the latter part of the afternoon and after the second pouring, but more often it begins soon after leaving the shop or in the early evening. (This we think is due to a diminished activity of the sweat glands after leaving the overheated shop.) l'rcc perspiration, by favoring an excretion of zinc, not only aids in aborting the chill but noticeably diminishes the intensity and duration of ail attack. l*'or this reason the men resort to hot drinks, the most efficacious, one of our patients told us, being hot milk with red pepper. For the same reason the men wrap themselves in blankets. The first thing complained of is a creepy, chilly sensation up and down the spine which gradually extends throughout the entire body. It may continue as a mere chilliness, but more often develops into a genuine rigor which lasts for from one-half hour to an hour or even from two to three hours. At its height, cramps and pains in the limbs are apt to occur; abdominal pain is infrequent, except as it may follow the ingestion of cold drinks. The pulse is increased in frequency and there is a slight elevation of temperature. Preceding the chill there is a dry, scratchy sensation in the throat, a sticking, pricking feeling IUESMAX, boles: spelter chills :;79 in the tongue, oppression in the chest, and an irritating cough, usually unproductive. Actual dyspnea is rare. There is a feeling of prostration and of nausea which frequently eventuates in severe vomiting. Diarrhea is common; indeed, the men at all times have a tendency to diarrhea, constipation being rare among brass molders. As the attack subsides the patient, quite exhausted, breaks out into copious perspiration and soon falls into a deep sleep. A temporary loathing for food and an unpleasant metallic taste in the mouth arc present on awakening and last a little while. One of us exposed himself for two afternoons to the fumes and flakes of zinc oxide during the melting and pouring process. In a few minutes the above-mentioned irritative condition in the throat and chest, with coughing, was experienced. Headache also de¬ veloped, and later a slight diarrhea. No chilliness, however, was felt. The attacks do not often incapacitate the workers. For this rea¬ son, and also because the men accept the “chills” as a matter of course and of no moment, the physician rarely has the opportunity of witnessing an attack.
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